49ers’ Patrick Willis shakes off rust for playoffs

After missing three games with a Grade 2 hamstring strain, Willis was back in the starting lineup Sunday in a 34-27 win over the Rams. Willis finished with four tackles, his lowest total in a full game this season, and the five-time Pro Bowler said he felt sluggish after not playing since Dec. 4.

“It felt great to be back out there,” Willis said. “Obviously I didn’t feel the same as I felt before I left. I felt my feet were real heavy. It felt different – like it was new all over again.”

Willis said it was important for him to play before the playoffs. He didn’t want to rest and run the risk of having a subpar performance in the postseason.

“I got a chance to go back out there today and kind of knock off some of that rust that I need to knock off,” Willis said.

No turnovers, again: A new era of 49ers football was marked by a stunning lack of errors.

The 49ers tied the NFL record for the fewest interceptions in a season (five), matched the 2010 Patriots for the fewest turnovers in a season since 1941 (10) and ended the season without committing a turnover in 22 straight quarters. Their plus-28 turnover differential matched the 2010 Patriots for the second-best total in the NFL since 1970.

San Francisco scored 14 points off interceptions by cornerback Tarell Brown on Sunday. Opponents haven’t scored a point off a 49ers turnover since San Francisco’s 25-19 win over Detroit on Oct. 16.

Kicking their way to records: San Francisco’s Andy Lee, who dropped punts of 66 and 64 yards inside St. Louis’ 9-yard line, set a single-season NFL record with a net-punting average of 43.99 yards, breaking the mark of 43.85 set by Oakland’s Shane Lechler in 2009. Lee led the NFL with a 50.9-yard gross average this season, the third-best mark in NFL history.

David Akers set single-season NFL records for most field-goal attempts (52) and for the most points by a kicker (166), breaking the mark of 164 set by Minnesota’s Gary Anderson in 1998.

Injuries: Fullback Bruce Miller left the game in the first half with a knee injury but later returned and, at times, played with a slight limp. Defensive tackle Ray McDonald left the game with what he said was a hamstring injury he didn’t believe was serious.

Smith fills in capably: With Ted Ginn and Kyle Williams sidelined by injuries, safety Reggie Smith, the No. 3 punt returner, stepped in and averaged 9.3 yards on four returns, including a 14-yarder.

Smith, a four-year veteran who had three punt returns in 2009, returned 67 punts during his college career at Oklahoma.